/Engine/Plugins/Protocols/MQTT/Source/MQTTCore/Public/MQTTClientObject.h
Initialize from C++ subscription
void Initialize ( const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FMQTTSubscription](API\Plugins\MQTTCore\FMQTTSubscription), ESPMode::ThreadSafe > & InSubscription )